To read this content please select one of the options below:

Modelling concrete slabs subjected to localised fire action with OpenSees

Mhd Anwar Orabi (Department of Building Services Engineering, The Hong Kong Polytechnic University, Kowloon, China)
Jin Qiu (Department of Building Services Engineering, The Hong Kong Polytechnic University, Kowloon, China)
Liming Jiang (Department of Building Services Engineering, The Hong Kong Polytechnic University, Kowloon, China)
Asif Usmani (Department of Building Services Engineering, The Hong Kong Polytechnic University, Kowloon, China)

Journal of Structural Fire Engineering

ISSN: 2040-2317

Article publication date: 22 April 2022

Issue publication date: 15 February 2023

239

Abstract

Purpose

Reinforced concrete slabs in fire have been heavily studied over the last three decades. However, most experimental and numerical work focuses on long-duration uniform exposure to standard fire. Considerably less effort has been put into investigating the response to localised fires that result in planarly non-uniform temperature distribution in the exposed elements.

Design/methodology/approach

In this paper, the OpenSees for Fire framework for modelling slabs under non-uniform fire exposure is presented, verified against numerical predictions by Abaqus and then validated against experimental tests. The thermal wrapper developed within OpenSees for Fire is then utilised to apply localised fire exposure to the validated slab models using the parameters of an experimentally observed localised fire. The effect of the smoke layer is also considered in this model and shown to significantly contribute to the thermal and thus thermo-mechanical response of slabs. Finally, the effect of localised fire heat release rate (HRR) and boundary conditions are studied.

Findings

The analysis showed that boundary conditions are very important for the response of slabs subject to localised fire, and expansive strains may be accommodated as deflections without severely damaging the slab by considering the lateral restraint.

Originality/value

This work demonstrates the capabilities of OpenSees for Fire in modelling structural behaviours subjected to non-uniform fire conditions and investigates the damage pattens of flat slabs exposed to localised fires. It is an advancing step towards understanding structural responses to realistic fires.

Keywords

Acknowledgements

The research is supported by the State Key Laboratory of Disaster Reduction of Civil Engineering Open Fund (Project No. SLDRCE20-02) and by the Start-up Fund of the Hong Kong Polytechnic University (Project No. P0031564). The financial support is gratefully acknowledged.

Citation

Orabi, M.A., Qiu, J., Jiang, L. and Usmani, A. (2023), "Modelling concrete slabs subjected to localised fire action with OpenSees", Journal of Structural Fire Engineering, Vol. 14 No. 1, pp. 128-145. https://doi.org/10.1108/JSFE-05-2021-0033

Publisher

:

Emerald Publishing Limited

Copyright © 2021, Emerald Publishing Limited

Related articles